To model a ratio, take the correct numbers of tiles from the box and create a set of tiles: |

For example ... the ratio of yellow to blue is 4 to 1 ... take out four yellow tiles and one blue tile and place them in a row. |

Now, add another row like the first. There is still 1 blue tile for every four yellow tiles, however we have used 10 tiles in all. Keep adding more rows and listing the equivalent ratios. |

To extend this to percents, simply keep adding tiles in the correct ratios until you have used 100 tiles in all (per means out of, and cent means one hundred). Now answer the questions: how many are yellow (80, thus 80%), and how many are blue (20, thus 20%). |

Find four equivalent ratios for each: 2 to 3 3 to 7 3 to 1 |

Estimate, calculate or model the percentage of each colour in the three ratios above. |